“(Nat. Geo. April 13, 2012) For the first time, astronomers have snapped photos of auroras lighting up Uranus's icy atmosphere.
Two fleeting, Earth-size auroral storms were imaged by the Hubble Space Telescope as they flared up on the dayside of the gas giant in November 2011.
"The last time we had any definite signals of auroral activity on Uranus was when NASA's Voyager 2 probe swung by in 1986," said study leader Laurent Lamy, an astronomer at the Observatoire de Paris in Meudon, France.
"But this is the first time we can actually see these emissions light up with an Earth-based telescope."
Uranus Auroras Seen in Stroke of Luck
Auroras are light displays often seen at the highest latitudes of Earth, Jupiter, and Saturn—all of which all have magnetospheres that act as shields against incoming solar storms.
Auroras tend to surround a planet's poles, where magnetic field lines converge and funnel incoming charged solar particles into the planet's atmosphere. There, the particles collide with air molecules, making the molecules glow.
Scientists tried unsuccessfully to detect auroras on Uranus in 1998 and 2005. In September 2011, Lamy and his team learned of an impending solar storm directed toward Uranus, which sits about 2.5 billion miles (4 billion kilometers) from Earth…”